Means for tight jointing the piston rings of internal-combustion engines



F. DUFAY AND M. BILLONI MEANS FOR TIGHT JOINTING THE PISTON RINGS OF INTERNAL COMBUSTION ENGINES. APPLICATION FILED JUNE 23. 1919.

2 SHEETS-SHEET I.

Fig.1 I

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I 21/ van Z 0119 F. DUFAY AND M. BILLON. MEANS FOR TIGHT JOINTING THE PISTON RINGS OF INTERNAL COMBUSTION ENGINES- APPLICATION FILED JUNE 23. 1919.

Patented A r. 25, 1922 2 SHEETS-SHEET 2.

fizz/anions M. B ill/ 02v "v ED ufwy By fltty FRANCOIS DUF AY AND MARCEL BILLON, OF PARIS, FRANCE.

MEANS FOR TIGHT JOINTING PISTON RINGS OF INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent. Patented Apr. 25, 1922.

Application filed June 23,1919. Serial No. 306,174.

(GRANTED UNDER THE PROVISIONS OF THE AC'LOE MARCH 3, 1921,41 STAT. L, 1313.)

To all whom it may concern:

Be it known that we, FRANgoIs DUFAY and 'MA CEL BILLON, citizens of the French Re-.

public, residing at 8 Rue Gustave Dor, Paris, France, have invented certain new and useful Improvements in Means 'for Tight J ointing the Piston Rings of Internal-Combustion Engines, (for which I have filed applications in France Jan. 19, 1918; Feb. 18, 1918; Dec. 2, 1918; Jan. 31, 1919; Belgium, May 1, 1919; Ital May 2, 1919; Switzerland, May 2, 1919; reat Britain, May 17, 1919, Patent No. 126,976, July 2, 1920,) of which the following is a specification.

This invention relates to means designed to remedy the want of tightness which generally occurs in the piston rings of internal combustion engines having fixed or rotating cylinders, steam engines, pumps, compressors, etc.

It is known that in engines having fixed or rotatingcylinders, the elasticity and the flexibility of the piston rings are often insufficient to allow them to follow the deformations of the cylinders and to make a tight joint betweeen the latter and the pistons.

Further, since the piston rings are interrupted at their ends, which interruption is not removed, by scarfing the rings, the joint is not always tight. The general result of this, especially in cylinders which have become worn or oval, or deformed by differences of expansion, by the heating of the engine, is an excessive consumption of carburetting mixture and oil, a considerable loss of power, a bad turning over of the engine when going dead slow, and the sooting of the cylinders and sparking plugs; this sooting being particularly apparent in engines having aluminium pistons.

The means for making a tight joint forming the subject matter of the present invention obviates these drawbacks and allows of remedying 1 The want of tightness towards gas and oil which is generally the case with the piston rings of internal combustion engines having fixed or rotating cylinders, steam engines, pumps, compressors, etc., owing to their insufficient elasticity, by the combination of two or three truncated conical rings in each piston groove; each combination including an internal truncated, conical, or bi-truncated conical ring which may be corrugated or not, acting upon the other or the other two conical or bi-truncated conical rings so as to force it or them against the sides of the cylinder, thereby causing the formation of a thin film of lubricant which is necessary and sufiicient for lubrication, and preventing the leakage of the gases between the cylinder and the piston.

One constructional form of this means is illustrated by way of example inthe accompanying drawings in which Fig. 1 is a vertical cross section of the aforesaid combination of two non-corrugated truncated conical piston rings for an internal combustion engine having rotating cylinders; the rings being shown in the position they occupy when the said rings and the piston are at rest.

Fig. 2 is a view similar to Fig. 1 showing the rings during the operation of the piston.

Fig. 3 is anelevation partly in section of a corrugated press ring for an engine having fixed or rotating cylinders.

Fig. 4 is a section of the combination of the corrugated press ring shown in Fig. 3,c0mbined with the jointing ring adapted to be opened out by it.

Fig. 5 is a vertical section of an arrangement in which the press ring is corrugated or non-corrugated, and has two truncated conical faces working upon two corresponding truncated conical faces of the jointmg ring.

Fig. 6 is a vertical section of the combination of a corrugated press ring, having two truncated conical faces working upon two rings, each of which has a truncated conical face and serves for making the joint.

In the construction shown in Figs. 1 and 2, the groove 0 in a. piston of an internal combustion engine having rotating cylinders contains two split rings a, b. a is preferabl made of steel and has an upwardly and inwardly inclined outer annular face,

nular face. The inclined face of the ring a V is of truncated conical form, with an angle a. The inner face of the ring b is likewise of truncated conical form with the same angle a. Against the latter there bears elastically the truncated conical face of the ring a. The height of this ring as isless than the height of the groove 0 in the piston, so that on compressing the inner ring for the purpose of bringing its ends into contact-with each other and on pushing it in this position into the interior of the hollow cone of the jointing ring b, there is still left a certain amount of play between its upper face and the u per face of the groove. 'The depth of t the steel ring a be able to touch the piston except when at rest.

When the cylinders are rotated, the centrifugal component F'of the forces of in-' ertia acting upon the press ring a causes the latter to move away from the lower face of the groove, and to enter into the interior of the hollow cone of b. This entrance causes first the mutual approach and then the meeting of its out ends so that they cannot slide over each other or become askew to each other.

From this moment onwards the ring a constitutes a closed ring acting in the manner of a circular wedge so as to open out and press the ring b against the sides of a 5 thus compelling it to follow the deformations of the cylinder, and assurin the tightness of the joint, notwithstan ing its friction against the upper part of the groove and the tangential 'force of inertia tending to create said friction.

the cylinder with a force=F cotan In rotary engines, and more particularly in the pistons of fixed engines, pumps, compressors, steam engines, etc., use may be made of the combination of a hollow truncated conical jointing ring, similar to the jointing ring 1) shown in Figs. 1 and 2, and a corrugated press ring a such as the one shown by way of example in Fig. 3, so that the insertion of this press ring into the groove, the placing of the cast iron ring I) into position, and the introduction of the whole into the cylinder (Fig; 4), will have the effect of compressing the win s or corrugations of the press ring towards the bottom of the groove, and cause these ends to become askew to each other and exert upon the said wings an. elastic force F directed towards the top of the piston. This force has the efiect of opening out and e groove must be sufficient to ensure that in no case shall" pressing the ring 2; against the sides of the cylinder with a force F. cotan independently of the action of centrifugal force in rotary engines, and the rec'procating forces of inertia in fixed engilies. the latter case, the force F may be sulficiently large so that the tightness of the joint, which is a maximum at its upper dead centre, shall be a minimum at the lower centre, thus varying in the same manner as the pressure of the gases in the cylinders.

Fig. 5 illusggates a constructional modification of this invention.' In this example the two rings a and b are provided with bi-conical cooperating faces. may be corrugated or not, and have any desired number of wings or corrugations. This ring a has two outer truncated conical faces acting upon the two corresponding inner truncated conical faces of the ring 12 Fig. 6 illustrates a construction wherein a corrugated steel ring at having an outer bitruncated conical surface and any desired number of wings or corrugations, has its ends brought together and its wings caused toyield under the action of the hollow truncated conical walls of the rings b and I), inserted into the cylinder. This flexure is the result of pressing the rings b and 1) against the upper and lower plane faces of the groove with an elastic pressure F and opening them out and pressing them against the sides of the cylinder with the respective pressures F cotan g and F cotan g, a and The ring a B being the respective angles of the hollow cones of the rings b and b. In this last construction a tight joint is assured against the gases and the oil leakingbetween the cylinder and the ring, and between the ring and the two plane. walls of the grooves,

independently of the action of the reciprocating forces of inertia when thepiston is moving.

Claims:

1. The combination with a piston having an annular groove in its cylindrical wall, of

a split ring located in said groove and having a conical inner face which is inclined upwardly toward the axis of the piston, and a second split ring located in the groove and having an outer conical face. complementary inner conical face which is inclined down-' I wardly toward the axis of the pistom and in which'the'second ring 'has an onter coniwhich the second ring has an outer conical cal face complementary to and cooperating 10 face complementary to and cooperating with with the'las't named conical face of the first the last named conical face of the first ring. ring, said firstring comprising a plurality 3. A combination as defined in'claim 1 in of annular superposed sections.

which the first ring is provided with an in- 4 ner concial face which is inclined downa, FRAN OIS DUFAY,

wardly toward the axis of the piston; and MARC L BILLON. 

